Do neckties actually reduce blood supply to the brain?

July 20, 2018 by Steve Kassem, The Conversation
The fashion advice is generally to tighten ties so they’re tight but not too tight. Credit: www.shutterstock.com

News reports about a study from Germany may provide the ultimate excuse for men to dress more casually for work, finding neckties reduce blood supply to the brain.

The study showed that wearing a tie that causes slight discomfort can reduce blood flow to the brain by 7.5%, but the reduction is unlikely to cause any physical symptoms, which generally begin at a reduction of 10%.

How was the research conducted?

Past research shows that compression of the in the neck reduces blood flow to the brain. In this new study, published recently in the journal Neuroradiology, the researchers tested whether the of a necktie could induce these changes.

They recruited 30 young men aged 21 to 28 years and split them into two groups: those wearing neckties and those without.

Using (MRI), the researchers tested the (total blood flow to the brain) using a technique that showed changes to the flow via a colour change. They also tested the blood flow from their jugular vein.

The first MRI took a "baseline" scan, while the participants in both groups had an open collar (and those in the tie-wearing group had a loosened tie).

For the second scan, the men's collars were closed and participants in the tie group tightened their Windsor knot until they felt slight discomfort.

A third scan followed, in the same conditions as the baseline scan. All scans lasted 15 minutes.

What did they find?

The authors found that wearing a necktie with a Windsor knot tightened to level of slight discomfort for 15 minutes led to a 7.5% drop in cerebral blood flow, and a 5.7% drop in the 15 minutes after the tie was loosened.

The men's blood flow in the control group – those who weren't wearing a tie – didn't change.

No change was found in jugular venous flow between the two groups.

What does it mean?

The study didn't go into any detail about the effects, so let's consider what they might be.

The researchers found a reduction in blood flow to the brain of 7.5%, which is unlikely to cause problems for most men.

Healthy people are likely to begin experiencing symptoms when blood flow to the brain reduces by about 10% – so, a larger reduction than the study found. Along with an increase in blood pressure at the site, a 10% reduction in blood flow can cause dizziness, light-headedness, headaches and nausea.

But even with a 7.5% drop in blood loss to the brain, a person could still experience some temporary dizziness, headaches or nausea.

Compounded with other factors, such as smoking or advanced age, a 7.5% decrease could bring some people over this 10% threshold of blood flow loss, placing extra stress on their already strained bodies and increasing their risk of losing consciousness or developing high-blood pressure.

It's unclear why there was no change to the jugular, but this may be due to the circular nature of the restriction: the pressure is equally distributed across the neck, rather than just the jugular.

What else do we need to take into account

Further research is needed to assess the impact of wearing a tie for longer periods and wearing different knots.

Any pressure on the neck is slightly discomforting, and men's style guides advise tightening a necktie to be "tight but not too tight". Whether this tightness aligns with the participants' classification of "slight discomfort" is unclear.

This study had a sample size of 30 participants, which is relatively small. Most human studies investigating blood pressure and cerebral blood have at least 40 to 60 participants.

Another limitation is that the study did not include a discussion about the potential impact of the blood restriction, or the finding that jugular flows didn't change.

But overall, the study is simple and well-designed. It adds to a small but growing body of research about the problems with neckties: they can lead to higher rates of infection, as they're infrequently washed; and they may increase intraocular pressure ( in the eyes) to the point of increasing the risk of glaucoma.

"Perhaps it's time to get rid of this unwelcome guest from our wardrobe, or restrict it to special occasions." – Steve Kassem

Blind peer review

"This is a fair and accurate assessment of the research. But it's important to note that 40% of the – those without neckties – also reported a decrease in cerebral . This could be a stress response. In future studies, we need larger sample sizes combined with longer durations to verify these findings." – Yugeesh Lankadeva

Explore further: Children with kidney disease show blood flow changes in brain

Related Stories

Children with kidney disease show blood flow changes in brain

June 12, 2018
Blood flow changes in the brains of children, adolescents and young adults with chronic kidney disease may explain why many face a higher risk of cognitive impairment, according to a study published online in the journal ...

Medical imaging technology detects vascular disorders, injuries in brain without invasive contrast agents

June 5, 2018
Purdue University researchers have developed an analytical imaging technology based on functional MRI for detecting and monitoring cerebral vascular disorders and injuries that does not require the use of contrast agents.

Oxygen therapy could help combat dementia in individuals with lung disease

July 5, 2018
Breathing in additional oxygen improves the function of blood vessels in the brain of people with breathing difficulties caused by lung conditions, according to new research published in Experimental Physiology. These findings ...

Why do we develop high blood pressure?

March 9, 2017
Abnormally high blood pressure, or hypertension, may be related to changes in brain activity and blood flow early in life. That's according to a study conducted on a rat model of high blood pressure, published in Experimental ...

Microbleeds, diminished cerebral blood flow in cognitively normal older patients

July 13, 2015
A small imaging study suggests cortical cerebral microbleeds in the brain, which are the remnant of red blood cell leakage from small vessels, were associated with reduced brain blood flow in a group of cognitively normal ...

Human brain has coping mechanism for dehydration

July 28, 2014
(HealthDay)—Although dehydration significantly reduces blood flow to the brain, researchers in England have found that the brain compensates by increasing the amount of oxygen it extracts from the blood. The findings were ...

Recommended for you

New exercise guidelines: Move more, sit less, start younger

November 12, 2018
Move more, sit less and get kids active as young as age 3, say new federal guidelines that stress that any amount and any type of exercise helps health.

Some activity fine for kids recovering from concussions, docs say

November 12, 2018
(HealthDay)—Children and teens who suffer a sports-related concussion should reduce, but not eliminate, physical and mental activity in the days after their injury, an American Academy of Pediatrics report says.

How many calories do you burn? It depends on time of day

November 9, 2018
Researchers reporting in Current Biology on November 8 have made the surprising discovery that the number of calories people burn while at rest changes with the time of day. When at rest, people burn 10 percent more calories ...

Yelp reviews reveal strengths and weaknesses of emergency departments and urgent care

November 9, 2018
Yelp reviews reveal that emergency departments are viewed as being higher quality but lacking in service as compared to urgent care centers, which patients rate the opposite, according to a new study from researchers in the ...

A look at how colds and chronic disease affect DNA expression

November 8, 2018
We're all born with a DNA sequence that encodes (in the form of genes) the very traits that make us, us—eye color, height, and even personality. We think of those genes as unchanging, but in reality, the way they are expressed, ...

Patients with untreated hearing loss incur higher health care costs over time

November 8, 2018
Older adults with untreated hearing loss incur substantially higher total health care costs compared to those who don't have hearing loss—an average of 46 percent, totaling $22,434 per person over a decade, according to ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

RobertKarlStonjek
5 / 5 (1) Jul 20, 2018
The study only evaluated physiological changes and ignored cognitive changes and changes in cognitive ability. The unrestricted blood flow is obviously the flow the brain requires for normal functioning, after all, the blood is used for cognitive processes, not for physiological functions like cooling the blood as Descartes once postulated.

With a lower blood flow you would expect peripheral attention to suffer. The peripheries are the least necessary and the first to go when focal attention is called for. Noticing whatever else is happening when you are thinking about something and multi-tasking are likely to be effected first when blood flow is restricted, that is, a person is likely to lean toward narrow mindedness, unimaginativeness, and less complete thinking when blood flow is restricted. A desire to conserve restricted resources is the likely brain response thus leading to more reluctance to think and contemplate generally, less likely to think outside the box etc.
Anonym518498
1 / 5 (1) Jul 22, 2018
another bogus study to support people dressing like slobs

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.